AC Joint Separation

Definition

The acromioclavicular (AC) joint is between the upper part of the shoulder blade and the collarbone. AC joint separation happens when the ligaments of this joint become damaged or torn. This causes a separation between the shoulder blade and the collarbone.

Risk Factors

Factors that may increase your chance of an AC joint separation include:

Playing certain sports, such as football, hockey, or lacrosse

Sports that may involve falls like cycling, skiing, or gymnastics

Increased age

Symptoms

Symptoms may include:

Tenderness or pain over the joint

Swelling

Bruising

A popping sensation in the joint

A bump on the shoulder

Diagnosis

You will be asked about your symptoms, medical history, and related accident. A physical exam will be done. It may include range-of-motion tests of the shoulder. The diagnosis can be made when there is an obvious deformity of the joint.

Revision Information

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.